//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// <unordered_map>

// template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
//           class Alloc = allocator<pair<const Key, T>>>
// class unordered_map

// iterator erase(const_iterator first, const_iterator last)

#include <unordered_map>
#include <string>
#include <cassert>
#include <iterator>

#include "test_macros.h"
#include "min_allocator.h"

int main(int, char**) {
  {
    typedef std::unordered_map<int, std::string> C;
    typedef std::pair<int, std::string> P;
    P a[] = {
        P(1, "one"),
        P(2, "two"),
        P(3, "three"),
        P(4, "four"),
        P(1, "four"),
        P(2, "four"),
    };
    C c(a, a + sizeof(a) / sizeof(a[0]));
    C::const_iterator i = c.find(2);
    C::const_iterator j = std::next(i, 1);
    C::iterator k       = c.erase(i, i);
    assert(k == i);
    assert(c.size() == 4);
    assert(c.at(1) == "one");
    assert(c.at(2) == "two");
    assert(c.at(3) == "three");
    assert(c.at(4) == "four");

    k = c.erase(i, j);
    assert(c.size() == 3);
    assert(k == j);
    assert(c.at(1) == "one");
    assert(c.at(3) == "three");
    assert(c.at(4) == "four");

    k = c.erase(c.cbegin(), c.cend());
    assert(k == c.cend());
    assert(c.size() == 0);
    assert(k == c.end());
  }
  { // Make sure that we're properly updating the bucket list when we're erasing to the end
    std::unordered_map<int, int> m;
    m.insert(std::make_pair(1, 1));
    m.insert(std::make_pair(2, 2));

    {
      auto pair = m.equal_range(1);
      assert(pair.first != pair.second);
      m.erase(pair.first, pair.second);
    }

    {
      auto pair = m.equal_range(2);
      assert(pair.first != pair.second);
      m.erase(pair.first, pair.second);
    }

    m.insert(std::make_pair(3, 3));
    assert(m.size() == 1);
    assert(*m.begin() == std::make_pair(3, 3));
    assert(++m.begin() == m.end());
  }
#if TEST_STD_VER >= 11
  {
    typedef std::unordered_map<int,
                               std::string,
                               std::hash<int>,
                               std::equal_to<int>,
                               min_allocator<std::pair<const int, std::string>>>
        C;
    typedef std::pair<int, std::string> P;
    P a[] = {
        P(1, "one"),
        P(2, "two"),
        P(3, "three"),
        P(4, "four"),
        P(1, "four"),
        P(2, "four"),
    };
    C c(a, a + sizeof(a) / sizeof(a[0]));
    C::const_iterator i = c.find(2);
    C::const_iterator j = std::next(i, 1);
    C::iterator k       = c.erase(i, i);
    assert(k == i);
    assert(c.size() == 4);
    assert(c.at(1) == "one");
    assert(c.at(2) == "two");
    assert(c.at(3) == "three");
    assert(c.at(4) == "four");

    k = c.erase(i, j);
    assert(c.size() == 3);
    assert(k == j);
    assert(c.at(1) == "one");
    assert(c.at(3) == "three");
    assert(c.at(4) == "four");

    k = c.erase(c.cbegin(), c.cend());
    assert(k == c.cend());
    assert(c.size() == 0);
    assert(k == c.end());
  }
#endif

  return 0;
}
